The study used epidemiological data on periodontal disease collected with a household survey of the U.S. population which describe the prevalence, severity and extent of periodontal diseases. These epidemiological data were then used to estimate the periodontal treatment needs of the U.S. as well as the time and dollars required to provide the treatment. Data from this study suggest that a decline in treatment methods have resulted in a reduction in periodontal treatment needs when compared with estimates from earlier epidemiologic studies. Only a small percentage of the population was found to have advanced periodontal disease, often involving only a few teeth, that required complex treatment. The vast majority of treatment needed was for the treatment of gingivitis, for prevention, and for the maintenance of periodontal health. When viewed from the perspective of expenditures, the annual cost to provide needed scaling and surgery to the entire population would be slightly less than 6% of the total expenditures for dental care in 1985.